The goals of this proposal build from results obtained in the previous 4 years of funding during which it was observed that combinations of fetal spinal cord transplants, neurotrophin treatment, and treatment with antibodies against the myelin inhibitory protein IN-1 significantly improved both regeneration of specific descending pathways and motor behavior in neonatal spinal lesioned rats. The hypothesis on which the present proposal is based are that interventions that increase anatomical regrowth of severed axons lead to increased functional recovery and specific descending pathways are differentially affected by these treatments and underlie distinct components of the behavioral recovery. In this proposal, the effects of these treatments will be examined in adult rats with spinal cord injury, examing 1) acute thoracic, 2) acute cervical, and 3) chronic cervical injury, evaluating both anatomical and behavioral recovery.